1. Field of the Invention
The present invention relates generally to agricultural lighting, and more particularly to agricultural light housings, and still more particularly to a grow light housing having ventilation slots for passive ventilation and reflective elements disposed over the ventilation opening, the combination configured in such a way as to capture and disperse light energy that would otherwise be lost.
2. Background Discussion
Indoor hydroponic and soil-based plant growing systems are now indispensable tools in both horticulture and agriculture. Large scale indoor growing systems are employed to provide produce out of season or in otherwise unsuitable climates, as well as to provide highly controlled growing conditions that optimize plant health and product yield, as well as to minimize exposure to risk of loss from insect and other herbivorous pests, frosts, hail, and so forth.
Indoor plant growing systems include, as essential elements, plant nutrient media and their containers, climate (humidity and temperature) control, lighting, and hydration. Large or full-sized plants, and those indigenous to latitudes and growing regions characterized by long periods of light sufficient for photosynthesis, frequently require high intensity lights, preferably full spectrum, for optimal growing conditions. However, high intensity lights generate considerable waste heat that can create injurious high temperatures in the immediate vicinity of the plants under the high intensity light. Additionally, high intensity lights give rise to temperature differentials throughout a facility in which diverse species are grown under varying lighting conditions. Thus, when exacting control over temperature in the growing environment is important, a cooling system may be employed to siphon off and eliminate waste heat and thereby to prevent a general rise in temperature in the growing facility and to prolong bulb life.
Solutions to the foregoing problem have been provided in the form of large systems that cool arrays of lights, and to individual cooling systems, generally in the form of fans and venting.
For instance, U.S. Pat. No. 6,247,830, to Winnett, et al., teaches an air-cooled light fixture having a transparent borosilicate glass cylinder surrounding a high intensity lamp. Attached to the ends of the cylinder are end plates for supporting the light fixture from a ceiling, each having a hose flange for connecting a hose to each end plate. On the inside wall of the transparent cylinder is a thermal protector device for disconnecting electrical power to the high intensity discharge lamp when a temperature inside the transparent cylinder reaches a predetermined temperature limit.
U.S. Pat. No. 6,595,662, to one of the present inventors, Wardenburg, discloses a double-walled grow light housing with air flow cooling system having an exterior shell with an air inlet and a hot air exhaust outlet, and a specular interior insertable into the shell. The sides of the specular insert are spaced apart from the walls of the shell so as to form a double-walled housing having air cooling chambers and vents which facilitate the movement and exhaust of air heated by high intensity light bulbs. The specular insert is configured with sides that cooperate with the shell to form air cooling spaces, and includes vents that allow hot air to circulate away from the bulb and outwardly into the air cooling chambers. There the air mixes with cooler air drawn into the cooling chambers through air inlets in the exterior shell; after mixing the air is vented upwardly and out through a hot air exhaust in the shell.
U.S. Pat. Appl. Pub. No. 20090116250, by Hargreaves, shows an aerodynamic lamp socket assembly including a lamp socket and a grow lamp positioned and attached within a horticulture light fixture to split a cooling stream of air around the lamp socket and grow lamp reducing cooling air resistance, turbulence, and disturbance.
U.S. Pat. Appl. Pub. No. 20080205071, by Townsley, discloses a lighting apparatus that includes an outer housing with an intake vent and an exhaust vent, an inner housing disposed within the interior of the outer housing, and an air path between the outer housing and the inner housing. The outer housing includes a cover, a top and a plurality of side walls forming the interior, and the inner housing includes a top and a plurality of side walls that correspond to the top and plurality of side walls of the outer housing. The air entering the outer housing through the intake vent travels along the air path and exits the outer housing through the exhaust vent.
U.S. Pat. Appl. Pub. No. 20040240214, by Whitlow, teaches a light fixture with an outer housing and an inner housing disposed within the outer housing and a lamp socket attached to the inner housing. An opening in the outer housing connects to a ventilation system and channels between walls and sides of the outer and inner housings receive air from the ventilation system through the opening, wherein a dedicated cooling system cools only the area immediately surrounding the plant or plants under the high intensity light.
The foregoing patents and published patent applications reflect the current state of the art of which the present inventors are aware. Reference to, and discussion of, these references is intended to aid in discharging Applicants' acknowledged duties of candor in disclosing information that may be relevant to the examination of claims to the present invention. However, it is respectfully submitted that none of the above-indicated patents disclose, teach, suggest, show, or otherwise render obvious, either singly or when considered in combination, the invention described and claimed herein.